Running the JNA tests against Firebird 2.1.7 + fbclient 2.1.7 with Flamerobin connected to the server prevents the crash, but a lot of tests still fail. Against 2.1.7 + fbclient 2.5.5 only a few tests fail (possibly using new service features). Looks like it might actually be a problem with the client library.

Mark Rotteveel added a comment - 09/Dec/15 01:14 PM Running the JNA tests against Firebird 2.1.7 + fbclient 2.1.7 with Flamerobin connected to the server prevents the crash, but a lot of tests still fail. Against 2.1.7 + fbclient 2.5.5 only a few tests fail (possibly using new service features). Looks like it might actually be a problem with the client library.

Excluded the JNA tests, uninstalled fbclient.dll from machine, tests still make Firebird 2.1.7 crash at random; I can't discount the possibility that this is a Windows 10 (and previously Windows 8) incompatibility of Firebird 2.1.7.

Problem was caused by not reading the response to op_detach. Adding a read of those responses (and the responses to op_service_detach) fixed the crash. There are still some tests failing against 2.1.7 that require further investigation.